Ultrastrong Medium-Entropy Single-Phase Alloys Designed via Severe Lattice Distortion

© 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Détails bibliographiques
Publié dans:Advanced materials (Deerfield Beach, Fla.). - 1998. - 31(2019), 8 vom: 28. Feb., Seite e1807142
Auteur principal: Sohn, Seok Su (Auteur)
Autres auteurs: Kwiatkowski da Silva, Alisson, Ikeda, Yuji, Körmann, Fritz, Lu, Wenjun, Choi, Won Seok, Gault, Baptiste, Ponge, Dirk, Neugebauer, Jörg, Raabe, Dierk
Format: Article en ligne
Langue:English
Publié: 2019
Accès à la collection:Advanced materials (Deerfield Beach, Fla.)
Sujets:Journal Article ab initio calculation atomic bond distances lattice distortion medium-entropy alloys tensile properties
Description
Résumé:© 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Severe lattice distortion is a core effect in the design of multiprincipal element alloys with the aim to enhance yield strength, a key indicator in structural engineering. Yet, the yield strength values of medium- and high-entropy alloys investigated so far do not substantially exceed those of conventional alloys owing to the insufficient utilization of lattice distortion. Here it is shown that a simple VCoNi equiatomic medium-entropy alloy exhibits a near 1 GPa yield strength and good ductility, outperforming conventional solid-solution alloys. It is demonstrated that a wide fluctuation of the atomic bond distances in such alloys, i.e., severe lattice distortion, improves both yield stress and its sensitivity to grain size. In addition, the dislocation-mediated plasticity effectively enhances the strength-ductility relationship by generating nanosized dislocation substructures due to massive pinning. The results demonstrate that severe lattice distortion is a key property for identifying extra-strong materials for structural engineering applications
Description:Date Completed 25.02.2019
Date Revised 01.10.2020
published: Print-Electronic
Citation Status PubMed-not-MEDLINE
ISSN:1521-4095
DOI:10.1002/adma.201807142